Gas, e.g., exhaust gas, treatment devices such as catalytic converters, evaporative emissions devices, hydrocarbon scrubbing devices, diesel particulate traps, non-thermal plasma reactors, and the like, are employed in various applications to physically and/or catalytically treat environmentally unfriendly gas emissions. Such gas treatment devices incorporate a substrate, support, monolith, or brick, which includes a catalyst material coated thereon. A mounting device such as a retention material comprising an intumescent material, non-intumescent material, or a combination of both, is disposed about the substrate forming a retention material/substrate subassembly, prior to being inserted into the gas treatment device's housing.
Generally, the term “substrate”, as used herein, may be used to refer to any high temperature (i.e., temperatures up to about 1000° C.) material, such as ceramic, metallic foils, combinations thereof, and other materials, with ceramic preferred, which is formed to provide a great number of gas passages capable of allowing exhaust fluid flow therethrough. As mentioned, the substrate employed in the catalytic converter may comprise a ceramic material, which may be susceptible to breakage if forces produced during a stuffing operation exceed a threshold value. Moreover, breakage may result, for example, from a rotation of a major axis of the substrate relative to a major axis of the shell/housing and stuffing cone (which may also be referred to as a stuffing cone apparatus, assembly or simply as cone). Similarly, when two or more substrates are employed rotation relative to each other may cause breakage. Commonly, an operator of a stuffing machine is responsible for determining whether a substrate is aligned within the shell, or if two or more substrates are employed, for determining whether they are aligned in relation to each other. With no visual reference other than, for example, the substrate profile, this alignment is a difficult task, wherein an operator's misjudgment may result in breakage of the substrate.
Therefore, what is needed in the art is a reliable method of determining the alignment of a substrate relative to a shell and/or relative to other substrates being stuffed into a shell.